Laundry machine and controlling method therefor

ABSTRACT

A laundry machine is disclosed. The disclosed laundry machine comprises: a detergent container for storing detergent; a detergent pump for discharging the stored detergent to the outside of the detergent container; a detergent detection sensor for detecting introduced detergent in the detergent pump; and a processor for determining whether there is detergent on the basis of a detection result of the detergent detection sensor, wherein, when a preset event occurs, the processor controls the detergent pump to operate for a preset time, and detects detergent after an operation of the detergent pump by using the detergent detection sensor.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a 371 of International Application No. PCT/KR2019/009075 filed on Jul. 23, 2019, which claims priority to Korean Patent Application No. 10-2018-0086230 filed on Jul. 24, 2018, the disclosures of which are herein incorporated by reference in their entirety.

BACKGROUND 1. Field

The disclosure relates to a washing machine and a controlling method therefor. More particularly, the disclosure relates to a washing machine which discharges air introduced into the detergent pump to the outside and improves accuracy in detergent detection and a controlling method therefor.

2. Description of Related Art

general, a washing machine (i.e., laundry machine) is a device which uses water and detergent to remove foreign matter stained on the laundry. The washing machine may rotate a washing tub by using a driving force of a motor, and may proceed with a series of processes such as washing, rinsing, spin-drying, and the like.

The washing machine may store detergent in a detergent container, and may inform a user whether or not a refill of the stored detergent is required. However, when identifying whether or not a refill of the detergent is required according to the related art, there has been the problem of an error generating in the detection of detergent due to air introduced into the detergent pump and the washing machine identifying as requiring detergent refill even when refill of detergent is not necessary.

The disclosure provides a washing machine which discharges air introduced into the detergent pump to the outside and improves accuracy in detergent detection and a controlling method therefor.

SUMMARY

According to an embodiment, a washing machine includes a detergent container configured to store a detergent, a detergent pump connected to an outlet of the detergent container and configured to discharge the stored detergent outside the detergent container, a detergent detection sensor configured to detect detergent which is discharged from the detergent container and introduced into the detergent pump, and a processor configured to identify whether or not detergent exists based on a detection result of the detergent detection sensor, and the processor is configured to control, based on a preset event occurring, the detergent pump to operate during a preset time, and detect whether or not detergent exists by using the detergent detection sensor after the operation of the detergent pump.

According to an embodiment, a controlling method of a washing machine includes checking whether or not a preset event occurred, discharging a detergent stored in a detergent container for a preset time to outside of the detergent container by using a detergent pump, detecting detergent which is discharged from the detergent container and introduced into the detergent pump by using the detergent detection sensor, and identifying whether or not detergent exists based on the detection result.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating a brief configuration of a washing machine according to an embodiment of the disclosure;

FIG. 2 is a block diagram illustrating a detailed configuration of a washing machine according to an embodiment of the disclosure;

FIG. 3 is a diagram illustrating an example of a detecting detergent by a detergent detection sensor;

FIG. 4 is a flowchart illustrating a controlling method of a washing machine according to an embodiment of the disclosure; and

FIG. 5 is a flowchart illustrating in detail a process of identifying whether or not detergent exists when performing a washing operation according to an embodiment of the disclosure.

DETAILED DESCRIPTION

Terms used in the disclosure will be briefly described, and the disclosure will be described in greater detail.

The terms used in the embodiments of the disclosure are currently widely used general terms and identified in consideration of the functions in the disclosure. However, these terms may vary depending on intention, legal or technical interpretation, emergence of new technologies, and the like of those skilled in the related art. In addition, in certain cases, there may be some terms arbitrarily identified by an applicant, and in this case the meaning will be described in detail in the corresponding description. Accordingly, the terms used herein should not be construed simply by the designation of the term, but defined based on the meaning of the term and the overall content of the disclosure.

Various modifications may be made to the embodiments of the disclosure, and there may be various types of embodiments. Accordingly, specific embodiments will be illustrated in drawings, and the embodiments will be described in detail in the detailed description. However, it should be noted that the various embodiments are not for limiting the scope of the disclosure to a specific embodiment, but they should be interpreted to include all modifications, equivalents or alternatives of the embodiments included in the ideas and the technical scopes disclosed herein. In case it is determined that in describing embodiments, the detailed description of related known technologies may unnecessarily confuse the gist of the disclosure, the detailed description will be omitted.

Terms such as “first,” “second,” and so on may be used to describe a variety of elements, but the elements should not be limited by these terms. The terms are used only for the purpose of distinguishing one element from another.

A singular expression includes a plural expression, unless otherwise specified. It is to be understood that the terms such as “comprise” or “include” are used herein to designate a presence of a characteristic, number, step, operation, element, component, or a combination thereof, and not to preclude a presence or a possibility of adding one or more of other characteristics, numbers, steps, operations, elements, components or a combination thereof.

The term “washing machine” used herein may refer to an electronic device that automatically washes laundry, and removes foreign matter stained on the laundry through methods such as agitating wash water with the laundry after adding wash water mixed with detergent and water in the main body. Types of washing machine may include a vortex-type washing machine, a drum-type washing machine, an agitator-type washing, a detergent-free washing machine, or the like.

The embodiments of the disclosure will be described in detail below with reference to the accompanying drawings to assist in the comprehension of those of ordinary skill in the related art. However, the disclosure may be implemented to various different forms, and may not be limited to the embodiments described herein. Further, in the drawings, parts unrelated to the description have been omitted to clearly describe the disclosure.

The disclosure will be described in greater detail below with reference to the accompanying drawings

FIG. 1 is a block diagram illustrating a brief configuration of a washing machine according to an embodiment of the disclosure.

Referring to FIG. 1, the washing machine 100 may include a detergent container 110, a detergent pump 120, a detergent detection sensor 130, and a processor 140.

The washing machine 100 may perform an operation to remove a foreign matter stained on the laundry. Specifically, the washing machine 100 may use water and detergent to perform at least one operation from among a washing for removing foreign matter stained on laundry, a rinsing for washing the detergent and the removed foreign matter with clean water, and a spin-drying for removing moisture from laundry.

The detergent container 110 may store detergent, reserve detergent, fabric softener, rinse, bleaching agent, or the like. The detergent stored at this time may be a power detergent or a liquid detergent.

The detergent container 110 may include a first container containing detergent and a second container containing fabric softener or rinse. The detergent, fabric softener, rinse, or the like stored in each container may be individually provided to a washing tub (not shown), which accommodates laundry, at necessary points in time according to the operation of the washing machine.

The detergent container 110 may be disposed inside of the washing machine 100, and may be protruded outwards of the washing machine or separated from the washing machine 100 for a user to fill in the detergent or the like to each container of the detergent container 110 or to take out from each container of the detergent container 110.

The detergent pump 120 may discharge the detergent, the reserve detergent, the fabric softener, the rinse or the bleaching agent stored in the detergent container 110 to the outside.

The detergent pump 120 may include one or a plurality of chambers provided to receive the detergent discharged from the detergent container. On one-surface of the chamber, an outlet of the detergent container 110 may be connected, and on another one-surface of the chamber a flow path connecting to the washing tub may be connected. Then, the detergent or the like discharged from the detergent container by the detergent pump 120 may be discharged to the flow path connecting to the washing tub via a chamber within the detergent pump 120.

For example, the detergent pump 120 may include a first chamber which connects to the first container of the detergent container 110 and a second chamber which connects to the second container of the detergent container 110, and the detergent of the first container may be discharged through the flow path connected to the washing tub via the first chamber, and the softener or rinse of the second container may be discharged through the flow path connected to the washing tub via the second chamber.

In addition, the detergent pump 120 may individually discharge the detergent of the first container and the softener or rinse of the second container at the point-in-time when each of the detergent, the softener or rinse is required according to the operation of the washing machine 100.

For example, the detergent pump 120 may discharge the detergent of a first containing part to the flow path prior to a washing operation starting when a washing operation instruction with respect to the washing machine 100 is input, and discharge the softener or rinse of a second containing part to the flow path while the washing operation is in progress.

In addition, the detergent pump 120 may change a discharge time based on the control of the processor 140 when discharging the detergent, the reserve detergent, the fabric softener, the rinse, or the bleaching agent of the detergent container 110.

For example, the detergent pump 120 may discharge the detergent, the rinse, or the like for about 3 seconds based on the control of the processor 140 to sufficiently provide a detergent amount required in the washing operation of the washing machine. In addition, the detergent pump 120 may discharge the detergent, the rinse, or the like for about 0.5 seconds based on the control of the processor 140 to remove air introduced into the detergent pump 120.

Here, the reason for removing air introduced into the detergent pump is to prevent an error from occurring of when a detergent detection sensor 130 within the detergent pump 120 detects detergent, the detergent may not be accurately detected due to air introduced into the detergent pump 120. The detailed description with respect to the operation for removing the introduced air will be described below with reference to the operation of the processor 140.

The detergent detection sensor 130 may detect the detergent, the reserve detergent, the fabric softener, the rinse, or the bleaching agent introduced through the detergent pump 120 in the detergent container 110. The detergent detection sensor 130 may be installed in each chamber within the detergent pump 120. For example, the detergent introduced from the first container to the first chamber or the softener or rinse introduced from the second container to the second chamber may be detected.

The detergent detection sensor 130 may include a first electrode and a second electrode spaced apart from the first electrode, and detect the detergent based on a voltage measured in-between the first electrode and the second electrode.

For example, based on a liquid detergent being introduced from the detergent container 110 to the detergent pump 120, and the liquid detergent contacting the first electrode and the second electrode due to a water level of the liquid detergent rising, the detergent may be detected since electricity flows through the liquid detergent and the detergent detection sensor 130 is capable of measuring a certain voltage.

On the other hand, based on the liquid detergent contacting only one from among the first electrode or the second electrode due to the water level of the liquid detergent being low or not contacting both the first electrode and the second electrode, the detergent may not be detected since there is no electricity flowing and the detergent detection sensor 130 is incapable of measuring the voltage. The type of sensor measuring the detergent is not limited to the above-described type.

The processor 140 may be configured to control each configuration within the washing machine 100. Specifically, the processor may be implemented as a central processing unit (CPU), an application specific integrated circuit (ASIC), or the like. Further the processor 140 may be comprised of a plurality of CPUs.

The processor 140 may be configured to check whether or not the detergent or the like exists to prevent washing performance from declining due to the detergent, the reserve detergent, the fabric softener, the rinse, the bleaching agent, or the like stored in the detergent container being used in an washing operation and the amounts thereof reducing, but a refill of the detergent or the like not occurring and resulting in the detergent or the like being insufficient when performing a washing operation thereafter.

Because the detergent or the like discharged from the detergent container 110 is introduced into the detergent pump 120, the processor 140 may be configured to use the detergent detection sensor 130 disposed within the detergent pump 120 to detect the introduced detergent or the like, and identify whether or not detergent of the detergent container 110 exists based on a detection result.

In addition, the processor 140 may be configured to identify whether or not detergent exists when a specific event has occurred.

Specifically, the processor 140 may be configured to identify whether or not detergent exists when the washing machine 100 is initially turned-on, when the washing machine 110 is turned-off and then turned-on again, when the detergent container is detected, by a mounting detection sensor 150, as protruded outside the washing machine 100 or separated from the washing machine 100 and then disposed back at its original position, when a washing operation instruction of the washing machine 100 is input, or when the washing operation of the washing machine 100 is completed.

For example, when the washing machine 100 is initially turned-on, because there is a high likelihood that there is no detergent in the detergent container 110, there may be a need to check whether or not detergent exists. In addition, when the washing machine 100 is turned-off and then turned-on again, because there may be the likelihood of a change in detergent amount occurring due to the user filling in the detergent or the like in the detergent container 100 or taking out all or a portion of the detergent or the like contained in the detergent container 110 in-between the point-in-time when the washing machine was turned-off and the washing machine was turned-on, there may be a need to check whether or not detergent exists.

In addition, when the detergent container 110 is detected as being protruded outside of the washing machine 100 or separated from the washing machine 100 and then disposed back to its original position, because there may be the likelihood of change occurring in detergent amount due to the user filling in detergent or the like in the detergent container 110 or taking out all or a portion of the detergent or the like contained in the detergent container 110 after extracting or separating the detergent container 110, there may be a need to check whether or not detergent exists.

In addition, when the washing operation instruction of the washing machine 100 is input, because performance in washing operation may decline if detergent is insufficient in the detergent container 110, there may be a need to check whether or not detergent exists prior to performing the washing operation. In addition, when the washing operation of the washing machine 100 is complete, because change in detergent amount has occurred by using the detergent in the washing operation, there is a need to check whether or not detergent exists.

The processor 140 may be configured to, based on corresponding to any case from among the above-described cases, use the result detecting the detergent or the like from the detergent detection sensor 130 and identify whether or not there is detergent or the like stored in the detergent container 110. For example, when detergent or the like is not detected by the detergent detection sensor 130, the detergent or the like in the detergent container 110 may be identified as insufficient, and when detergent or the like is detected by the detergent detection sensor 130, the detergent or the like in the detergent container 110 may be identified as present.

When air is introduced with the detergent or the like from the detergent container 110 to the detergent pump 120, an error may occur when detecting the detergent. For example, based on the detergent being a liquid detergent with a high viscosity, and air is introduced with the liquid detergent from the detergent container 110 to the detergent pump 120, air may be present between a first electrode 1301 and a second electrode 130-2 of the detergent detection sensor 130, and the liquid detergent may be present in a remaining area not in contact with the first electrode 130-1 or the second electrode 130-2, as in FIG. 3A. In this case, although detergent may actually be sufficiently stored in the detergent container 110, the detergent may not be detected.

Accordingly, the processor 140 may be configured to, as a method for raising accuracy in detergent detection, control the detergent pump 120 to cause the detergent pump 120 to operate for a preset time to remove the air introduced together with the detergent in the detergent pump 120 prior to using the detergent detection sensor 130 to detect the detergent.

The processor 140 may be configured to control the detergent pump 120 to discharge the detergent stored in the detergent container 110 to the outside of the detergent container 110 for a preset time. The discharged detergent may be newly introduced to the chamber within the detergent pump 120, and the air which was previously introduced in the chamber may be discharged outside of the chamber being pushed by the newly introduced detergent.

For example, the processor 140 may be configured to control the detergent pump 120 to discharge the detergent, the softener or rinse stored in each of the first container and the second container for a preset time to each of the first chamber and the second chamber, and the detergent or the like newly introduced to each of the first chamber and the second chamber may push out the air which was previously introduced to the first chamber and the second chamber.

The preset time may be time required in pushing out detergent or the like and air within the detergent pump 120. The preset time may be set to be smaller than the time for discharging the detergent by the detergent pump 120 when performing the washing operation. In addition, the preset time may be a value calculated based on a result from repeated experimentations.

In addition, the processor 140 may be configured to, as another method of raising accuracy in detergent detection, control the detergent pump 120 to cause the detergent pump 120 to operate at a certain discharge intensity to remove the air introduced with the detergent in the detergent pump 120, prior to using the detergent detection sensor 130 to detect the detergent.

The processor 140 may be configured to control the detergent pump to operate at a discharge intensity smaller than the discharge intensity of the detergent pump 120 required during the washing operation. Accordingly, the discharged detergent may be smaller than the amount of detergent discharged during the washing operation. The discharged detergent may be newly introduced to the detergent pump 120, and the air previously introduced in the detergent pump 120 may be discharged outside the detergent pump 120 by being pushed by the newly introduced detergent.

For example, the processor 140 may be configured to control the detergent pump 120 to discharge the detergent, the softener or the rinse stored in each of the first container and the second container to each chamber at a discharge intensity smaller than the discharge intensity of the detergent pump 120 required when performing the washing operation. The detergent or the like newly introduced to each of the first chamber and the second chamber may push out air, which was previously introduced in the first chamber and the second chamber.

The method of removing air within the detergent pump 120 by using the detergent pump 120 to raise accuracy in detergent detection is not limited to the above-described method.

In addition, as described above, because the operation of the detergent pump 120 to remove the introduced air may be set so that the discharge time is smaller or the discharge intensity is smaller than the operation of the detergent pump 120 for the washing operation, the amount of the discharged detergent or the like may be smaller than the discharged amount for the washing operation.

The detergent discharged at this time may be used in the washing operation of the washing machine 100 hereafter. For example, the based on some detergent being discharged to remove introduced air, and then the washing operation instruction of the washing machine 100 being input and the detergent or the like being additionally discharged from the detergent container 110, the first discharged detergent may be provided to the washing tub mixed together with the additionally discharged detergent or the like.

The processor 140 may be configured to use the detergent detection sensor 130 after operating the detergent pump 120 to remove air introduced within the detergent pump 120 to detect the detergent.

The processor 140 may be configured to, based on controlling the detergent pump 120 to operate for a predetermined time, use the detergent detection sensor 130 to detect the detergent after verifying that the detergent pump 120 is no longer in operation due to the operation of the detergent pump 120 during the predetermined time being completed.

Here, the reason for detecting the detergent after verifying that the detergent pump 120 is no longer in operation is to raise accuracy in detergent detection taking into consideration the time spent by the detergent in moving from the detergent container 110 to the inside of the detergent pump 120.

For example, based on the detergent corresponding to one type of a liquid detergent with a high viscosity, even if the detergent is discharged from the detergent container, it may take time until the detergent reaches the detergent detection sensor. Accordingly, based on the detergent pump 120 detecting the detergent while in operation, a case may arise of the detergent not being detected due to detergent detection occurring in a state in which the detergent is in contact with only one electrode of the detergent detection sensor 130, as in FIG. 3B.

Accordingly, the accuracy of detergent detection may be raised if the detergent is detected after verifying that the operation of the detergent pump 120 has been completed and is no longer in operation.

In addition, the processor 140 may be configured to use the detergent detection sensor 130 after passing of a predetermined time to detect the detergent after verifying that the operation of the detergent pump 120 during the predetermined time has been completed and that the detergent pump 120 is no longer in operation.

In this case, more time may be provided to a case where the detergent introduced to the detergent pump 120 may contact both electrodes of the detergent detection sensor 130, than to a case where the detergent detection sensor 130 is used to detect the detergent directly after verifying that the detergent pump 120 is no longer in operation.

Accordingly, the detergent detection sensor 130 not being able to detect the detergent due to a lack of time, which is required for the detergent to contact both electrodes of the detergent detection sensor 130, may be more effectively prevented.

The processor 140 may be configured to identify whether or not detergent exists based on the result of detecting the detergent by using the detergent detection sensor 130 after the operation of the detergent pump 120 to remove the air introduced within the detergent pump 120.

The processor 140 may be configured to use the detergent detection sensor 130 to consecutively detect detergent multiple times, and aggregate the detected result of multiple times to identify whether or not detergent exists. The identifying the detergent multiple times is to raise accuracy in detergent detection taking into consideration the time spent by the detergent moving from the detergent container 110 to the inside of the detergent pump 120.

For example, based on the detergent corresponding to a type of liquid detergent with high viscosity, even if the detergent is discharged from the detergent container 110, because of time spent until the detergent contacts the first electrode and the second electrode of the detergent detection sensor 130 due to the high viscosity of the detergent, the detergent detection sensor 130 may not be able to detect the detergent when detecting for the detergent a first time.

However, when the detergent is detected consecutively at predetermined time intervals multiple times, even if the detergent has not been detected due to the detergent not yet being in contact with the first electrode 130-1 and the second electrode 130-2 of the detergent detection sensor 130 when performing detergent detection at a first time as in FIG. 3A or FIG. 3B, the detergent may be detected in contact with both the electrodes 130-1 and 130-2, respectively, when performing the detergent detection thereafter as in FIG. 3C.

In this case, the processor 140 may be configured to use the detection result of multiple times, consider as having taken time until the discharged detergent is in contact with both electrodes of the detergent detection sensor 130, and identify the detergent as existing. The method of using the detection result of multiple times to identify whether or not detergent exists is not limited to the above-described method.

The processor 140 may be configured to, based on identifying as there being no detergent in the detergent container 110, provide a detergent refill required notification message to the user. Specifically, the processor may be configured to use a display 190 to display the detergent refill notification message to the user, or use a buzzer (not shown) to provide the user with a notification sound. The method of providing, to the user, a notification on requiring a detergent refill is not limited to the above-described method.

In describing FIG. 1, the detergent container 110 has been described as capable of including the first container and the second container, but may include one container or three or more containers at implementation, and the subject stored in each of the first container and the second container may not be limited to detergent, softener, rinse, or the like.

FIG. 2 is a block diagram illustrating a detailed configuration of a washing machine according to an embodiment of the disclosure.

Referring to FIG. 2, the washing machine 100 may include a detergent container 110, a detergent pump 120, a detergent detection sensor 130, a processor 140, a amounting detection sensor 150, a driving device 160, a memory 170, an input device 180, and a display 190. Parts overlapping with the above-described description will be omitted below and described.

The mounting detection sensor 150 may detect whether the detergent container 110 has been disposed back to its original position after being protruded outside of the washing machine 100 or separated from the washing machine 100. The mounting detection sensor 150 may be disposed at one side-surface of the detergent container 110 or a one side-surface of the washing machine 100 corresponding to the position to which the detergent container 110 is coupled with the washing machine 100.

The driving device 160 may perform various functions of the washing machine 100. For example, the driving device may perform functions such as, for, example, and without limitation, washing, rinsing, spin-drying, or the like with respect to the laundry accommodated in the washing tub (not shown). To this end, the driving device 160 may include a motor (not shown), a heater (not shown), a pump (not shown), or the like. The driving device 160 may drive the motor (not shown) when a wash instruction is received, drive the heater (not shown) when a spin-dry instruction is received, and drive the pump (not shown) when a rinse instruction is received.

The memory 170 may store instructions or data related to at least one other element of the washing machine 100. The memory 170 may be implemented as, for example, and without limitation, a non-volatile memory, a volatile memory, a flash-memory, a hard disk drive (HDD), a solid state drive (SDD), or the like.

The memory 170 may be accessed by the processor 140, and reading/writing/modifying/deleting/updating or the like of data may be performed by the processor 140. The term memory used herein may include a memory 170, a read only memory (ROM) within the processor 140, a random access memory (RAM), or a memory card (not shown) mounted to the washing machine 100 (e.g., a micro secure digital (SD) card, a memory stick).

The memory 170 may store the detection result of the detergent detection sensor 130. For example, the memory 170 may be configured to, based on the detergent detection sensor 130 detecting the detergent by using the first electrode and the second electrode, store a voltage value measured when detecting the detergent.

Accordingly, the processor 140 may use the stored voltage value to calculate an intrinsic resistance value of the detergent and store the calculated value in the memory 170. Because the object contacting the first electrode and the second electrode of the detergent detection sensor 130 performs the role of variable resistance, the processor 140 may be configured to calculate the variable resistance value of the object which is in contact with the first electrode and the second electrode if the measured voltage value was used.

For example, when the liquid detergent is in contact with the first electrode and the second electrode, the voltage value measured by the detergent detection sensor 130 may be used to calculate the intrinsic resistance value of the liquid detergent. On the other hand, when the liquid detergent is not contact with the first electrode and the second electrode due to lack of liquid detergent and only air is in contact, a nearly infinite resistant value may be calculated.

Accordingly, the processor 140 may calculate the resistance value with respect to the contact object of the detergent detection sensor 130, and store the calculated resistance value in the memory 170.

In addition, because the detergent has an intrinsic resistance value based on the type, the processor 140 may be configured to calculate the intrinsic resistance value of the detergent inserted into the detergent container 110 to identify what type of detergent it is. Then, the processor 140 may be configured to, when controlling the operation of the detergent pump 120 to remove the air introduced into the detergent pump 120, control the detergent pump taking into consideration the viscosity being different according to the type of detergent. Specifically, the processor 140 may be configured to adjust the discharge time or discharge intensity of the detergent pump 120 according to the type of the identified detergent.

For example, based on being identified as a detergent with low viscosity, the processor 140 may be configured to control the detergent pump 120 to discharge for 0.3 seconds to remove the air which is introduced within the detergent pump 120, and based on being identified as a detergent with high viscosity, the processor 140 may be configured to control the detergent pump 120 to discharge for 0.5 seconds.

In addition, based on being identified as a detergent with low viscosity, the processor 140 may be configured to control the detergent pump 120 to operate at a discharge intensity smaller than when being identified as a detergent with high viscosity.

To this end, the memory 170 may store information on the intrinsic resistance value for each detergent type, and store information on the discharge time of the detergent pump 120 corresponding to the intrinsic resistance value. Then, the processor 140 may be configured to check the information on the discharge time of the detergent pump corresponding to the calculated resistance value, and control the detergent pump 120 to operate during a discharge time of the detergent pump 120 corresponding to the calculated resistance value.

The memory 170 may store the detection result of the mounting detection sensor 150. For example, information on the point-in-time at which the detergent container 110 is protruded to the outside of the washing machine 100 or separated from the washing machine 100, information on the point-in-time at which the detergent container 110 is disposed back at its original position, and the like may be stored.

The detergent may be exposed to air as it is stored in the detergent container 110, and the viscosity of the detergent may gradually increase as time elapses. Accordingly, the processor 140 may be configured to, when controlling the operation of the detergent pump 120 to remove air introduced into the detergent pump 120, control the detergent pump taking into consideration the likelihood of the viscosity of the detergent changing due to an elapse-in-time.

The processor 140 may use information on the point-in-time at which the detergent container 110 was last disposed at the original position to calculate an elapse-in-time up to the present after the detergent container 110 has been disposed to its original position, and use the calculated elapse-in-time to adjust the discharge time or the discharge intensity of the detergent pump 120.

For example, based on the calculated elapse-in-time being shorter than a predetermined time, the processor 140 may be configured to control the detergent pump 120 to operate for 0.3 seconds to remove the air introduced within the detergent pump 120, and based on the calculated elapse-in-time being longer than the predetermined time, the processor 140 may be configured to control the detergent pump 120 to operate for 0.5 seconds.

In addition, based on the calculated elapse-in-time being shorter than the predetermined time, the processor 140 may be configured to control the detergent pump 120 to operate at a discharge intensity smaller than when the calculated elapse-in-time is longer than the predetermined time.

The predetermined time may refer to time it takes for the viscosity of the detergent exposed to air changing. The predetermined time may be identified based on repeated experimentations. The discharge time or discharge intensity of the detergent pump 120 may also be adjusted based on a section for each time slot of the calculated elapse-in-time.

In addition, the processor 140 may adjust the discharge time or discharge intensity of the detergent pump 120 taking into consideration all of the different viscosities based on the types of the above-described detergent and the likelihood of viscosity changes in the detergent based on the elapse-in-time.

The memory 170 may be configured to, based on the processor 140 identifying whether or not detergent exists, store to identified result.

Accordingly, the processor 140 may be configured to, based on the washing operation instruction of the washing machine 100 being additionally input after the identified result on whether or not detergent exists is stored, use the identified result stored in the memory 170 to identify whether or not detergent exists without controlling to perform the above-described operation of the detergent pump 120 and the operation of the detergent detection sensor 130 to identify whether or not detergent exists.

In addition, the processor 140 may be configured to, based on no additional washing operation instruction being input after the identified result on whether or not detergent exists is stored and the washing machine 100 is turned-off and then turned-on again, use the identified result stored in the memory 170 to identify whether or not detergent exists without controlling to perform the above-described operation of the detergent pump 120 and the operation of the detergent detection sensor 130 to identify whether or not detergent exists.

Then, the processor 140 may identify whether or not to refill the detergent based on the stored result. The processor 140 may be configured to, when checking that the detergent is insufficient through stored result, identify as a refill of the detergent being required, and when checking that the detergent is sufficient through the stored result, identify as a refill of the detergent not being required.

The input device 180 may receive input of a function selection and a control instruction on the corresponding function from the user. The function herein may refer to a washing function, a rinsing function, a spin-drying function, or the like.

For example, the user may select the washing function through the input device 180, and input an instruction to use the wash water of a temperature of 65 degrees Celsius.

The input device 180 may be implemented as a plurality of physical buttons, a switch, or the like, and may also be implemented as a touch screen capable of simultaneously performing a display function.

The display 190 may be configured to display various information provided by the washing machine 100. Specifically, the display 190 may be configured to display a user interface window for the various function provided by the washing machine 100 to be selected. The display 190 may be a monitor, such as a liquid crystal display (LCD), a cathode ray tube (CRT), or an organic light-emitting diode (OLED), and may also be implemented as a touch screen capable of simultaneously performing the above-described function of the input device 180.

The display 190 may be configured to display a detergent refill required notification message to the user. For example, when a refill of detergent is required, an image of a detergent container shape may be displayed to flicker periodically to convey the detergent refill required notification to the user.

Although not illustrated in FIG. 2, the buzzer (not shown) may be further included. The buzzer (not shown) may be configured to, when the processor 140 has identified as requiring a refill of detergent, output a notification sound requesting a refill to the user.

In describing FIG. 2, the embodiment has been described as detecting with respect to the detergent identifying whether or not detergent exists, storing the identification result of whether or not detergent exists, displaying the results, and the like, but the above-described operations may be performed with respect to not only the detergent but also the fabric softener, the rinse, or the bleaching agent upon implementation.

Until recently, because detection of the detergent was not properly detected due to air introduced into the detergent pump being present when the detergent detection sensor detects the detergent, there has been the problem of an error of identifying a refill of detergent being required occurring despite there being sufficient detergent in the detergent container.

However, as described above, because the detergent pump is used to partially discharge the detergent in the detergent container to discharge the air within the detergent pump to the outside of the detergent pump prior to detecting the detergent in the detergent detection sensor, there may be the effect of improving the detergent detection accuracy of the detergent detection sensor.

FIG. 3 is a diagram illustrating an example of detecting detergent by a detergent detection sensor.

Referring to FIG. 3, the detergent pump 120 may include a chamber 121 provided to receive the detergent discharged from the detergent container 110 inside the detergent pump 120. In addition, although omitted from the drawing, an outlet of the detergent container 110 is connected to a one-surface of the chamber 121, and a flow path connecting to the washing tub may be connected to the other one-surface of the chamber 121. The detergent or the like stored in the detergent container 110 may be introduced to the chamber 121 within the detergent pump 120 through the outlet and provided to the washing tub through the flow path. In addition, the detergent detection sensor 130 may be disposed within the chamber 121. The detergent detection sensor 130 may include the first electrode 130-1 and the second electrode 130-2 which is spaced apart from the first electrode 130-1.

FIG. 3A illustrates an example of the detergent detection sensor 130 not being able to detect the detergent when detergent and air is introduced together into the chamber 121 of the detergent pump 120.

For example, if the detergent is a liquid detergent with high viscosity and the liquid detergent with air is introduced from the detergent container 110 to the detergent pump 120, air may be present in-between the first electrode 130-1 and the second electrode 130-2 of the detergent detection sensor 130 due to the viscosity of the liquid detergent, and liquid detergent may be present in the remaining area that is not in contact with the first electrode 130-1 and the second electrode 130-2. In this case, although detergent may actually be sufficiently stored in the detergent container 110, the detergent may not be detected.

FIG. 3B illustrates an example of the detergent detection sensor 130 not being able to detect the detergent despite the detergent being additionally introduced to the chamber 121 through the operation of the detergent pump 120.

As described above, the processor 140 may be configured to control the detergent pump 120 for a certain time to remove the air introduced within the chamber 121, and control to cause the detergent detection sensor 130 to detect the detergent when the operation is complete.

However, in the case of the detergent being a liquid detergent with high viscosity, despite the detergent being additionally introduced to the chamber 121 due to the operation of the detergent pump 120, it may take time until the detergent reaches both electrodes 130-1 and 130-2 of the detergent detection sensor 130 due to the viscosity of the liquid detergent. Accordingly, the detergent detection sensor 130 may detect the detergent prior to the liquid detergent contacting both the first and second electrodes 130-1 and 130-2.

FIG. 3C illustrates an example of the detergent being detected through the detergent detection sensor 130

Based on the detergent contacting the first electrode 130-1 and the second electrode 130-2 of the detergent detection sensor 130, electricity may flow through the detergent and the detergent detection sensor 130 may detect the detergent.

In illustrating and describing FIG. 3, the detergent detection sensor has been illustrated and described as detecting or the like with respect to the detergent, but the detergent detection sensor may perform the above-described operations with respect to not only detergent, but also fabric softener, rinse, or bleaching agent upon implementation.

In addition, in illustrating and describing FIG. 3, the chamber has been described as a quadrangle shape and the first electrode and the second electrode has been described as a long rod shape as an example and illustrated, but is not limited thereto upon implementation.

FIG. 4 is a flowchart illustrating a controlling method of a washing machine according to an embodiment of the disclosure.

First, whether or not a preset event has occurred may be checked (S401). The preset event may be a situation which requires checking of whether or not detergent exists.

Specifically, the preset event may include when the washing machine is initially turned-on, when the washing machine is turned-off and then turned-on again, when the detergent container is detected by the mounting detection sensor as being protruded outside the washing machine or separated from the washing machine 100 and then disposed back to its original position, when the washing operation instruction of the washing machine is input, when the washing operation of the washing machine is completed, or the like.

Then, when a preset event occurs, the detergent pump may be used to discharge the detergent stored in the detergent container for a preset time to the outside of the detergent container (S402).

When air is introduced with the detergent from the detergent container to the detergent pump, an error may occur when the detergent detection sensor detects the detergent. Accordingly, as a method for raising accuracy in detergent detection, the detergent stored in the detergent container may be discharged outside the detergent container by using the detergent pump for a preset time, prior to detecting the detergent using the detergent detection sensor.

The detergent discharged from the detergent container maybe newly introduced to the detergent pump, and the air which was previously introduced into the detergent pump may be discharged outside the detergent pump by being pushed by the newly introduced detergent.

The preset time may be time required to push out the detergent or the like and the air within the detergent pump. The preset time may be set to be smaller than the time it takes for the detergent pump to discharge the detergent when performing the washing operation. In addition, the preset time may be a value calculated based on repeated experimentations.

In addition, as another method for raising accuracy in detergent detection, the detergent pump may be controlled to cause the detergent pump to operate at a smaller discharge intensity than the discharge intensity required when performing the washing operation to remove air introduced with the detergent within the detergent pump, prior to detecting the detergent by using the detergent detection sensor.

The detergent discharged from the detergent container may be smaller than the detergent amount discharged when performing the washing operation, may be newly introduced to the detergent pump, and the air which was previously introduced into the detergent pump may be discharged outside of the detergent pump by being pushed out by the newly introduced detergent.

Then, the detergent detection sensor may be used to detect the detergent introduced into the detergent pump (S403).

The detergent detection sensor may be disposed within the detergent pump. The detergent detection sensor may be discharged outside of the detergent container by an operation of the detergent pump and may detect the detergent introduced into the detergent pump.

In addition, the detergent detection sensor may include the first electrode and the second electrode spaced apart from the first electrode, and may detect the detergent based on the voltage measured in-between the first electrode and the second electrode.

In addition, the operation for detecting the detergent may be performed after verifying that the operation of the detergent pump for a preset time is completed and the detergent pump is no longer in operation. This is to raise accuracy in detergent detection taking into consideration the time it takes for the detergent to move from the detergent container to the inside of the detergent pump.

In addition, the operation of detecting the detergent may be performed after the passing of a predetermined time even after verifying that the operation of the detergent pump for a preset time has been completed and that the detergent pump is no longer in operation.

In this case, rather than the method of detecting the detergent by using the detergent detection sensor immediately after verifying that the detergent pump is no longer in operation, the time it takes until the detergent discharged from the detergent container is capable of contacting the detergent detection sensor may be longer. Accordingly, the detergent detection sensor not being able to detect the detergent due to a lack of time, which is required for the detergent to contact the detergent detection sensor, may be more effectively prevented.

Then, whether or not the detergent exists may be identified based on the detergent detection result (S404). When the detergent is detected, the detergent may be identified as existing, and thereby identified as not requiring a detergent refill. On the other hand, when the detergent is not detected, the detergent may be identified as being insufficient, and thereby identified as requiring a detergent refill. When identified as requiring a refill of detergent, the display, the buzzer, or the like may be used to provide a detergent refill required notification to the user.

In addition, when detergent is detected multiple times consecutively by using the detergent detection sensor, the detection result of multiple times may be used to identify whether or not detergent exists. This is to raise accuracy in detergent detection taking into consideration the time it takes for the detergent to move from the detergent container to the detergent pump.

In addition, after identifying whether or not the detergent exists, the identified result may be stored. If after storing the identified result and a washing operation instruction of the washing machine is additionally input, the stored identified result may be used to identify whether or not detergent exists without controlling to perform the above-described operation of the detergent pump and the operation of the detergent detection sensor to identify whether or not the detergent exists.

In addition thereto, even when the additional washing operation instruction is not input after storing the identified result and the washing machine is turned-off and then turned-on again, the stored identified result may be used to identify whether or not the detergent exists without controlling to perform the above-described operation of the detergent pump and the operation of the detergent detection sensor to identify whether or not the detergent exists.

The mounting detection sensor may be used to detect whether the detergent container has been disposed back to its original position after being protruded to the outside of the washing machine or separated from the washing machine, and the detection result may be stored. The stored detection result may include information on the point-in-time at which the detergent container was last disposed back to its original position after being protruded outside of the washing machine or separated from the washing machine.

Then, by using the information on the last point-in-time from among the information on the point-in-time the detergent container was disposed back to the original position, the elapse-in-time from after the detergent container was last disposed to its original position to present may be calculated. Then, the calculated elapse-in-time may be used to adjust the discharge time or discharge intensity of the detergent pump.

Then, the detergent pump may be controlled to cause the detergent stored in the detergent container to be discharged outside of the detergent container according to the adjusted discharge time or the discharge intensity.

In addition, the voltage value measured by using the detergent detection sensor may be stored. Then, an intrinsic resistance value stored in the detergent container may be calculated by using the stored voltage value, and the calculated value may be stored. In addition, information on the intrinsic resistance value for each type of the detergent may be stored, and information on the discharge time of the detergent pump 120 corresponding to the intrinsic resistance value may be stored.

In this case, the discharge time corresponding to the calculated intrinsic resistance value from among the information on the discharge time of the detergent pump 120 corresponding to the intrinsic resistance value may be checked, and the detergent pump 120 may be controlled to discharge the detergent of the detergent container to the outside of the detergent container according to the checked discharge time.

In illustrating and describing FIG. 4, although the embodiment has been illustrated and described as detecting with respect to the detergent, identifying whether or not detergent exists, storing or displaying of the identified result value, or the like, the above-described operations may be performed with respect to not only the detergent, but also the fabric softener, the rinse, or the bleaching agent upon implementation.

Accordingly, because the method of discharging the air introduced into the detergent pump to the outside prior to detecting the detergent prevents the detergent detection sensor from not being able to detect the detergent due to air, the method may have the effect of improving the accuracy in detergent detection. The controlling method, as in FIG. 4, may be executed on a washing machine with the configurations of FIG. 1 or FIG. 2, and also on washing machines with other configurations other than those described above.

In addition, the controlling method as described above may be implemented with at least one execution program for executing the controlling method as described above, and the execution program may be stored in a non-transitory computer readable medium.

The non-transitory computer readable medium refers to a medium that stores data semi-permanently rather than storing data for a very short time, such as, for example, and without limitation, a register, a cache, a memory, or the like, and is readable by an device. In detail, the above-described various applications or programs may be stored and provided in the non-transitory computer readable medium, such as, for example, and without limitation, a compact disc (CD), a digital versatile disc (DVD), a hard disc, a Blu-ray disc, a universal serial bus (USB), a memory card, a ROM, and the like.

FIG. 5 is a flowchart illustrating in detail a process of identifying whether or not detergent exists when performing a washing operation according to an embodiment of the disclosure.

First, a power of the washing machine may be applied (S501). Then, the washing operation instruction may be received from the user (S502). The operation instruction may be received through an input device or a display implemented as a touch screen.

Then, the detergent may be detected by using the detergent detection sensor, whether or not the detergent exists may be identified based on the detection result, and whether or not a refill of the detergent is required accordingly may be identified (S503).

Specifically, the detergent detection sensor may be disposed inside the detergent pump and detect the detergent introduced from the detergent container to the detergent pump. The detergent detection sensor may include the first electrode and the second electrode spaced apart from the first electrode, and may detect the detergent based on the voltage measured in-between the first electrode and the second electrode.

When the detergent introduced to the detergent pump is in contact with the first electrode and the second electrode, because electricity flows through the detergent and the detergent is detected, the detergent detection sensor may identify the detergent as existing, and identify as requiring a refill of detergent.

On the other hand, when the detergent is in contact with any one from among the first electrode or the second electrode or not in contact with both the first electrode and the second electrode, because electricity does not flow and the detergent is not detected, it may be identified as the detergent not existing and it may be identified a refill of detergent being required.

If, it is identified that a refill of detergent is not required (S503-N), the detergent may be inserted into the washing tub to perform the washing operation of the washing machine (S507).

On the other hand, if it is identified as a refill of detergent being required (S503-Y), a notification on requiring a refill of detergent may be provided to the user (S504). For example, an icon notifying that a refill of detergent is required may be displayed through the display or a notification sound notifying of a refill of detergent being required may be output through the buzzer.

Then, when the detergent container is disposed back to its original position in the washing machine after being protruded outside of the washing machine or separated from the washing machine, the detergent pump may be used to discharge the detergent stored in the detergent container to the outside and air which was introduced into the detergent pup may be removed (S505).

Specifically, when the detergent container is detected as protruding outside or separated from the washing machine through the mounting detection senor, there may be a likelihood of change in detergent amount occurring due to the detergent in the detergent container being filled in or a portion or all of the detergent in the detergent container being taken out. Accordingly, there is a need to check whether or not detergent exists, and the detergent pump may be used to remove air introduced into the detergent pump by discharging the detergent stored in the detergent container to the outside for a detergent detection of high accuracy.

Then the detergent detection sensor may be used to detect the detergent, whether or not detergent exists may be identified based on the detection result, and whether or not a refill of detergent is required may be identified (S506). The detergent at this time may correspond to one type of liquid detergent, and detergent detection may be carried out multiple times taking into consideration the time it takes for the detergent discharged from the detergent container to be introduced into the detergent pump. Then, the detection result of multiple times may be accumulated and whether or not a refill of detergent is required may be identified.

If it is identified as a refill of detergent not being required (S506-N), the detergent may be inserted into the washing tub to perform the washing operation of the washing machine (S507). On the other hand, if it is determined as a refill of detergent being required (S506-Y), a notification on requiring a refill of detergent may be provided again to the user (S504).

Then, after the detergent is inserted into the washing tub and the washing operation is performed, the detergent detection sensor may be used again to detect the detergent, and whether or not detergent exists may be identified based on the detection result to identify whether or not a refill of detergent is required accordingly (S508). To improve accuracy when detecting detergent, the detergent detection may be performed multiple times, whether or not detergent exists may be identified by using the detection result of multiple times, and whether or not a refill of detergent is required may be identified. In addition, if it is identified as a refill of detergent being required based on the detection result, the above-described steps S504 to S506 may be performed.

Then, the identified result on whether or not a refill of detergent required may be stored (S509). For example, if it is identified as requiring a refill, the result of requiring a refill may be stored, and if it is identified as not requiring a refill, the result of not requiring a refill may be stored.

After storing the identified result on whether or not a refill of detergent is required, if it is detected through the mounting detection sensor that the detergent container is disposed back to its original position after being protruded outside of the washing machine or separated from the washing machine, or an additional washing operation has been performed, there may be a likelihood of a change occurring to the detergent amount stored in the detergent container. Accordingly, the detergent detection sensor may be used again to detect the detergent, whether or not the detergent exists may be identified based on the detection result, whether or not a refill of detergent is required may be identified accordingly, and the identified result on whether or not a refill is required may be stored.

Then, when the washing machine is turned-off and then turned-on again (S501), a notification on whether or not a refill of detergent is required may be provided to the user based on the stored identified result of whether or not a refill of detergent is required.

For example, if the identified result on whether or not a refill of detergent is required stored prior to the washing machine being turned-off corresponds to requiring a refill, the washing machine may display an icon notifying to user that a refill of detergent is required through the display, or output a notification sound notifying that a refill of detergent is required through the buzzer.

On the other hand, when the identification result on whether or not a refill of detergent is required stored prior to the washing machine being turned-off corresponds to not requiring a refill, the washing machine may display an icon notifying to user that the detergent is stored through the display.

In illustrating and describing FIG. 5, the embodiment has been illustrated and described as detecting with respect to the detergent, identifying whether or not a refill is required, storing or displaying of the identified result value, or the like, but the above-described operations may be performed with respect to not only the detergent, but also the fabric softener, the rinse, or the bleaching agent upon implementation.

Accordingly, because the method of discharging the air introduced into the detergent pump to the outside prior to detecting the detergent prevents the detergent detection sensor from not being able to detect the detergent due to air, there may be the effect of improving accuracy in detergent detection. The controlling method as in FIG. 5 may be executed on a washing machine with configurations of FIG. 1 or FIG. 2, and may be executed on a washing machine with other configurations other than those described above.

In addition, the controlling method as described above may be implemented through at least one execution program for executing the controlling method as described above, and the execution program may be stored in a non-transitory computer readable medium.

While example embodiments have been illustrated and described above, the disclosure is not limited to the above-described specific embodiments, and it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope as defined, for example, by the following claims and their equivalents. 

1. A washing machine, comprising: a detergent container storing a detergent; a detergent pump connected to an outlet of the detergent container and configured to discharge the stored detergent to an outside of the detergent container; a detergent detection sensor configured to detect the detergent discharged from the detergent container and introduced into the detergent pump; and a processor configured to identify whether or not detergent exists based on a detection result of the detergent detection sensor, wherein the processor is configured to: control, based on a preset event occurring, the detergent pump to operate for a preset time, and detect whether or not detergent exists by using the detergent detection sensor after an operation of the detergent pump.
 2. The washing machine of claim 1, wherein the processor is configured to detect, based on the preset event occurring and the detergent pump not operating since an operation of the detergent pump has been completed for the preset time, whether or not the detergent exists by using the detergent detection sensor.
 3. The washing machine of claim 1, wherein the processor is configured to detect the detergent multiple times by using the detergent detection sensor after the operation of the detergent pump, and identify whether or not the detergent exists by using the detected result of multiple times.
 4. The washing machine of claim 1, further comprising: a mounting detection sensor configured to detect whether or not the detergent container is protruded outside of the washing machine or separated from the washing machine, wherein the preset event is at least one from among when the washing machine is initially turned-on, when the detergent container is detected, by the mounting detection sensor, as disposed back to its original position after being protruded to the outside of the washing machine or separated from the washing machine, when an washing operation instruction of the washing machine is input, or when a washing operation of the washing machine is completed.
 5. The washing machine of claim 4, further comprising: a memory configured to store information on a point-in-time at which the detergent container, which is detected by the mounting detector sensor, is disposed back to its original position after being protruded outside of the washing machine or separated from the washing machine, wherein the processor is configured to: calculate an elapse-in-time from after the detergent container is last disposed at it its original location to present by using information on a point-in-time at which the detergent container was last disposed at its original position from among information on a point-in-time the detergent container was detected stored in the memory, adjust the preset time by using the calculated elapse-in-time, and control the detergent pump to operate for the adjusted preset time based on the preset event occurring.
 6. The washing machine of claim 1, wherein the detergent detection sensor comprises a first electrode and a second electrode spaced apart from the first electrode, and detects the detergent introduced into the detergent pump by measuring a voltage value in-between the first electrode and the second electrode.
 7. The washing machine of claim 6, further comprising: a memory configured to store an intrinsic resistance value based on a detergent type and information on the preset time corresponding to the intrinsic resistance value, and store the voltage value measured with the detergent detection sensor, wherein the processor is configured to: calculating an intrinsic resistance value of the detergent by using the voltage value stored in the memory, check the preset time corresponding to the calculated intrinsic resistance value from among information on the stored preset time, and control the detergent pump to operate for the checked preset time based on a preset event occurring.
 8. The washing machine of claim 4, further comprising: a memory, wherein the processor is configured to: store, in the memory, an identified result after identifying whether or not the detergent exists, and identify, based on an additional washing operation instruction of the washing machine being input, whether or not the detergent exists by using the stored identified result.
 9. A controlling method of a washing machine, the method comprising: checking whether or not a preset event has occurred; discharging, based on the preset event being occurred, a detergent stored in a detergent container for a preset time to an outside of the detergent container by using a detergent pump; detecting the detergent which is discharged from the detergent container and introduced into the detergent pump by using a detergent detection sensor; and identifying whether or not the detergent exists based on the detection result.
 10. The method of claim 9, wherein the detecting the detergent comprises using the detergent detection sensor to detect the detergent introduced into the detergent pump based on an operation of discharging the detergent stored in the detergent container to the outside of the detergent container being completed and the detergent pump no longer operating.
 11. The method of claim 9, wherein the detecting the detergent comprises detecting the detergent introduced into the detergent pump multiple times after discharging to the outside, and wherein the identifying whether or not the detergent exists comprises identifying whether or not the detergent exists by using the detected result of multiple times.
 12. The method of claim 9, wherein the preset event is at least one from among when the washing machine is initially turned-on, when the detergent container is detected, by the mounting detection sensor, as disposed back to its original position after being protruded to the outside of the washing machine or separated from the washing machine, when an washing operation instruction of the washing machine is input, or when a washing operation of the washing machine is completed.
 13. The method of claim 9, further comprising: storing information on a point-in-time at which the detergent container is disposed back to its original position after being protruded outside of the washing machine or separated from the washing machine; using information on a point-in-time at which the detergent container was last disposed back to its original position after being protruded outside of the washing machine or separated from the washing machine to calculate an elapse-in-time from after the detergent container was last disposed at its original position to present; and adjusting the preset time by using the calculated elapse-in-time, wherein the discharging to the outside comprises discharging the detergent stored in the detergent container for the adjusted preset time to the outside of the detergent container.
 14. The method of claim 9, wherein the detergent detection sensor comprises a first electrode and a second electrode spaced apart from the first electrode, and detects the detergent introduced into the detergent pump by measuring a voltage value in-between the first electrode and the second electrode.
 15. The method of claim 14, further comprising: storing an intrinsic resistance value based on a detergent type and information on the preset time corresponding to the intrinsic resistance value; storing a voltage value measured with the detergent detection sensor; and calculating an intrinsic resistance value of the detergent by using the stored voltage value, and checking a preset time corresponding to the calculated intrinsic resistance value from among information on the preset time, wherein the discharging to the outside comprises discharging the detergent stored in the detergent container for the checked preset time to the outside of the detergent container. 